When using services in a terminal supporting a plurality of radio access interfaces, advantages and disadvantages of using the services vary depending on a wireless network connected using the corresponding radio access interface. For example, it is assumed that a terminal supports a wireless fidelity (Wi-Fi) interface and a cellular interface.
A Wi-Fi wireless network is free of charge, has a lower installation cost than that of a cellular wireless network, and generally provides high-speed performance. However, a Wi-Fi wireless network has limited accessible areas, and has a performance that rapidly deteriorates with an increase in the number of users. In contrast, a cellular wireless network charges for data usage and has a lower maximum available data rate than that of a Wi-Fi wireless network, but generally provides stable performance and has a wide coverage area. Especially, in a mobile environment, an Internet connection through a cellular wireless network is generally stable. As described above, the Wi-Fi interface and the cellular interface may be mutually complementary, although they clearly have their own advantages and disadvantages c.
In accordance with the development of mobile communication, a terminal has developed to support at least two radio access interfaces, but when an actual service is used, an Internet connection is established through only one interface. Generally, the use of the Wi-Fi interface as a primary interface is prioritized. Thereby, when a corresponding terminal moves to a location where access to a Wi-Fi network is possible, an Internet connection is performed through the Wi-Fi interface even though the actual speed of offered services is relatively high. In this case, the Wi-Fi wireless network may become relatively easily unstable in the wireless network situation. In addition, since the actual available service provision coverage itself is small, it may frequently cause a decrease in user-perceived quality with respect to higher services such as streaming services or the like.
In addition, the selection and conversion (connection manager) function itself of the radio access interface in a current terminal determines a radio access interface to be used according to a channel status indicator received through the corresponding wireless networks, for example, a Received Signal Strength Indication (RSSI), and therefore there is still a problem in terms of the user-perceived quality because the characteristics of the higher services such as streaming services or the like cannot be considered.
Thus, new Hypertext Transfer Protocol (HTTP)-based streaming schemes have been proposed in order to provide seamless video playback by determining video quality flexibly in response to changes in the wireless network. The New HTTP-based streaming schemes include an Adobe Systems scheme, an HTTP Dynamic Streaming scheme, an Apple HTTP Live Streaming scheme, an Microsoft Smooth Streaming scheme, an adaptive streaming scheme such as a Moving Picture Experts Group (MPEG)-Dynamic Adaptive Streaming over HTTP standard, an adaptive bit rate streaming scheme, and the like. While the new HTTP-based streaming scheme enables seamless video playback, it is fundamentally impossible to reproduce image quality beyond available bandwidth and it may cause a problem of deterioration of user-perceived performance due to frequent changes in the image quality. That is, it is difficult to fundamentally solve the performance degradation and fluctuation problem of the wireless network only by the adaptive streaming scheme.